92 MR. G. BENTHAM ON GRAMINEE. 
straight awns to the flowering glume, besides the long rigid 
twisted dorsal one, which, as well as the single flower, removes 
the genus from the Pappophore:e. 
37. Lacurus, Linn., is a well-known widely spread Mediter- 
ranean grass, which, like Trisetaria, has two slender awns to 
the flowering glume besides the more rigid dorsal one, but is 
well marked by the capitate inflorescence, to which the long hairs 
of the linear plumose empty glumes give a peculiar soft silky 
aspect. 
Tribe IX. IsACHNEZ, 
This small tribe is a modification of the subtribe I proposed 
in the * Flora Australiensis ’ under the name of Milieæ, and which 
I distinguished from Agrostez by the absence of the dorsal awn, 
and from Festuces by the single or two equal flowers in each 
spikelet ; and I included in the group both Milium and Sporo- 
bolus. Since I have worked up the Agrosteæ of the northern 
hemisphere, however, I find that the presence or absence of the 
dorsal awn is much more uncertain than I had thought, that 
Milium cannot be removed far from Oryzopsis, and that Sporo- 
bolus must be referred back to Agrostew. But there remain a 
group of genera, nearly related both to Agrostez and to Avene&, 
but never showing the dorsal awn so general in those tribes, 
and enclosing in each spikelet two equal flowering glumes and 
flowers, apparently inserted at the same point without any deve- 
lopment of the rhacbilla between them (except in Cælachne) and 
never any continuation beyond the flowers. The two flowers are 
both hermaphrodite and fertile; or occasionally only one of them, 
usually the upper one, is female or sterile. The tribe thus limited 
would consist of the following seven genera:— 
1. PRIONACHNE, Nees, subsequently republished by the same 
author under the name of Chondrolena, is a South-African annual 
with an almost simple terminal spike, distinguished by the outer 
empty glumes as long as the flowering ones, with a rigid pec- 
tinately-toothed cartilaginous keel. Atenosachne, Steud., is most 
probably the same plant. 
2. Isacune, Br. comprises about twenty tropical or subtro- 
pical species, chiefly from the Old World, but including a few 
American ones. The small spikelets with the loosely paniculate 
inflorescence and more or less hardened fruiting glumes give them 
the appearance nearly of some species of Panicum, to which 
